Review on decolorisation of aqueous dye solutions by low cost adsorbents

Textile wastewater presents a challenge to conventional physico-chemical and biological treatment methods. Liquid-phase adsorption has been shown to be highly efficient for the removal of dyes and other organic matters from process or waste effluent. Many different types of adsorbent are used to remove colour from wastewater among which the most widely used material is activated carbon. Since activated carbon is expensive and necessitates regeneration, attempts have been made to substitute alternatives that are biodegradable, low cost and/or waste materials. This article presents the investigations carried out by numerous researchers on the use of different kinds of adsorbents and their adsorption capacities for the removal of specific dyes from textile wastewater.